1. Field of the Invention
The present invention relates to a protective casing for electric distribution busbars.
2. Description of the Prior Art
In certain applications, it is necessary to place a protective casing of insulating material around an array of electric distribution busbars such as those encountered in electric cubicles.
In one design of electric cubicle which is already known, an array of main electric distribution busbars extends horizontally across the cubicle in its upper region. To this horizontal array is connected a vertical array which extends downwards to the bottom of the cubicle within a column provided with connecting means for mounting a number of different devices placed on each side of the column.
It is a known practice in this case to place at the top of the column a protective casing which closes the top of the column except for openings through which the vertical busbars can be connected to the main busbars. The purpose of this protective casing is to prevent conductive elements such as screws or washers from falling into the column when making a connection between the main array and the vertical array.
The protective casing is made up of two half-casings, one of which is provided on the periphery of its open face with recesses for receiving the busbars. The two half-casings are moved into position on each side of the vertical array and assembled together so as to imprison the busbars between them.
This system for protecting the upper ends of columns by means of half-casings of molded material involves the need to manufacture and store a large number of different half-casings. In fact, depending on the power transmitted, the busbars can have different dimensions corresponding to different dimensions of the casing which is in position. Provision must accordingly be made for two different half-casings for each dimension of busbars.
The aim of the invention is to propose a protective casing which minimizes the number of different half-casings to be manufactured and stored in order to meet all particular cases of installed power.